I'd also check out the Dropped Piano's EP. It's just as good as any Hecker LP and its only around the 30 minute mark. A lot of replay value. It's also great to listen to before Ravedeath because it's like it's little sister in terms of music: its similar but stands out enough on it's own to be a separate release.

Harmony is my second fave Hecker after Ravedeath. You can't go wrong naming any Hecker album as his best though tbh.